Vehicle energy management system

ABSTRACT

A vehicle energy management system relying on the principle of reallocation of existing resources provided by the vehicle manufacture. Engine belt or engine direct driven components are replaced with electrical motors. Since replacement of the main fan unit would involve a prohibitively large fan due to starting currents, the larger component that would have multiple cooling purposes is replaced with smaller single function electrical components. The larger multipurpose heat exchangers such as the vehicle radiator are replaced with smaller single function heat exchangers associated with the smaller electric fans. The energy management system may involve a main vehicle engine crankshaft mounted generator. This simple generator creates high voltage DC electricity that may be converted to household level AC for the operation of customer application equipment. In one embodiment, the converter is a closed loop converter that makes the conversion of DC to AC alternatively turning on and off at a varying frequency in order to produce a time averaged AC output.

This is a non-provisional patent application claiming the priority ofprovisional patent application Ser. No. 60/377,158, filed May 2, 2002.

BACKGROUND OF THE INVENTION

Modern commercial vehicles include conventional electrical supplysystems. These systems provide low voltage DC to vehicle manufacturerprovided systems. Most commercial vehicles are produced by an originalequipment manufacturer (OEM) and later are provided with customerequipment. The customer equipment could at one time have been poweredfrom the OEM provided electrical system without any strain on thesystem. The customer application equipment varies widely, howeverexamples would include refrigeration systems for produce deliveryvehicles or trucks to fire pumps for fire trucks to towing winches ontow trucks.

As the end user applications have grown so have their powerrequirements. Alternator capacity for the latest in medium-duty dieselpowered trucks is a 100-amp capacity. Heavy-duty trucks with home-likeconveniences such as microwave cooking ovens have a demand in the 2400watts range with a 164-amp alternator. For trucks with added customerapplication equipment, OEMs estimate total vehicle capacity will be 3000watts with the next generation of engine controls expected to demandmore. When the OEM electrical system capacity has been exceeded,customers have relied upon diesel powered auxiliary systems beyond thevehicles main engine or electro-hydraulic generators with hydraulicenergy supplied by an engine mounted power take-off (PTO) from thevehicle's main engine. The issues for these solutions include cost,system control, and lack of efficiency. An additional auxiliary dieselengine adds cost as well as inconvenience. The control would be separatefrom the main vehicle engine. Electro-hydraulic generators are directlinked to the main engine through the PTO. This is inefficient in thatenergy is wasted on these units even when the customer energyconsumption devices are not in use.

There is a need for an integrated vehicle energy management system thatprovides the energy for the increasing customer application needswithout reducing the overall vehicle energy efficiency and is controlledby an integrated control system.

SUMMARY OF THE INVENTION

One general object is to provide an integrated energy management systemfor providing the capacity to power increased customer application needswithout the need for an additional diesel engine. Additional objectsinclude improving the overall vehicle energy efficiency as well asproviding control to this added capacity that is integrated into anexisting on-board vehicle control system.

The vehicle energy management system of this invention provides anattractive solution to the objects of the invention as well as tocustomer and vehicle issues not mentioned. The energy management systemuses the main vehicle engine as the main provider of OEM provided andcustomer application equipment. Since the system does not mandate thatconventional engine capacity be increased, the energy management systemrelies on the principle of reallocation of existing resources providedby the OEM for efficient redistribution. Specifically, the systeminvolves the replacement of engine belt or engine direct drivencomponents with electrical motors. The engine-direct drive fan draws asmuch as 30-40 HP to operate. Since replacement of the main fan unitwould involve a prohibitively large fan due to starting currents, thelarger component that would have multiple cooling purposes is replacedwith smaller single function electrical components. The largermultipurpose heat exchangers such as the vehicle radiator are replacedwith smaller single function heat exchangers associated with the smallerelectric fans. An electric fan with the dedicated purpose of providingflow for engine coolant might draw 9-10 HP instead of the original 30-40HP of the direct mechanical drive fan. These heat exchangers and fansmay be mounted to the same vehicle component, an example being thechassis. This would allow for tighter tolerances between the fan andheat exchanger passages, thereby improving efficiency. The energymanagement system may involve a main vehicle engine crankshaft mountedgenerator. This simple generator creates high voltage direct current(DC) electricity. In one embodiment, this generator is mounted directlyto the forward portion of the crankshaft and also provides thecrankshaft dampening function. The high voltage DC may be converted tohousehold level AC (115VAC) for the operation of customer applicationequipment. In one embodiment, the converter is a closed loop converterthat makes the conversion of DC to AC alternatively turning on and offat a varying frequency in order to produce a time averaged AC output.The household or customer level AC is directed to the customerelectrical bus that is provided at the OEM level. A portion of thehousehold or customer level AC is converted to lower voltage DC throughtransformers or rectifiers. This low level DC is used to power cabinstruments and controls and higher level of this low level DC may beused for next generation engine controls. The design's use of the ON-OFFclosed loop or otherwise known as a switch mode converter in a vehicleis unique. Similarly, the energy management systems use of a largernumber of smaller single function heat exchangers and associatedelectric fans provides unique advantages such as flexibility about thelocation of the heat exchangers in areas other than the front of thevehicle and enhanced efficiency due to tolerance reduction with thecommon mounting areas for fans and heat exchangers. It is anticipatedthat there will be an associated improvement in fuel economy, as theindividual electric fans will not have to all run the same time. Theprior art direct drive fans and motors were constantly wind millingduring engine operation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is partial cutaway perspective view of a mobile vehicle with anembodiment of a vehicle energy management system installed and made inaccordance with the invention.

FIG. 2 is a top down view of the vehicle of FIG. 1.

FIG. 3 is a simplified block diagram of the electrical portion of theenergy management system of FIG. 1.

FIG. 4 is an embodiment of a heat exchanger and fan for use in theenergy management system of FIG. 1.

FIG. 5 is block diagram of another embodiment of the cooling systemportion of the energy management system.

FIG. 6 shows the output of the switch mode converter of the energyconverter of FIG. 3.

FIG. 7 shows a simplified block diagram of a second embodiment of anelectrical portion of the energy management system.

DETAILED DESCRIPTION

This invention describes a vehicle energy management system that movestowards electrification and separate sub-assembly cooling. The energymanagement system does not mandate that conventional engine capacity beincreased. The energy management system relies on the principle ofreallocation of existing resources provided by the vehicle originalequipment manufacture (OEM) for efficient redistribution. An examplevehicle 101 with an embodiment of the energy management system installedis shown in FIGS. 1 and 2. The vehicle 101 includes a chassis 102 and acab 103. The chassis 102 includes two parallel frame rail members 102 aand 102 b. An engine 104 for providing the motive force for the vehicle101 is engaged to the chassis 102. The driver and passenger control theengine 104 of the vehicle 101 from the cab 103. The engine 104 may havea flywheel structure with conventional 12 Volt starter 121. Much of thecustomer energy consumption equipment is installed to the chassis 102. Aforward axle assembly and suspension 111 are shown engaged to theforward portion of the chassis 102; the rearward portion of the chassis102 is not shown but includes at least one additional axle andsuspension assembly 111.

The energy management system involves the replacement of engine belt orengine direct driven components with electrical motors. Sincereplacement of the main fan unit would involve a prohibitively large fandue to starting currents, the larger component that would have multiplecooling purposes is replaced with smaller single function electrical fancomponents. The larger multipurpose heat exchangers such as the vehicleradiator are replaced with smaller single function heat exchangersassociated with the smaller electric fans. The system shown has separateheat exchangers for individual vehicle functions. There is atransmission heat exchanger 106, an engine coolant heat exchanger 107,an engine oil heat exchanger 109, an engine turbocharger heat exchanger110, and a heating, ventilation, and air conditioning (HVAC) heatexchanger 108. These heat exchangers and fans may be mounted to the samevehicle component, the chassis 102 for the vehicle 101 shown. Thisallows for tighter tolerances between the fan and heat exchangerpassages due to reduced vibration, thereby improving efficiency.

The transmission heat exchanger 106 and the HVAC heat exchanger 108 maybe mounted away from the front of the vehicle 101 so as to be locatedcloser to the components to be cooled. This could not be accomplished inthe prior art system where there was one main heat exchanger and chargeair cooler package. This was in the front of the vehicle to absorb theram air generated by vehicle movement. The energy management system ofthis invention allows the splitting of the heat exchangers to morelogical locations. The separate packaging of the heat exchangers willalso allow creative changes in the esthetics or aerodynamics of the hoodand vehicle front-end geometry.

FIG. 4 is one embodiment of the engine coolant heat exchanger 107 thatmay be used in the vehicle 101 energy management systems. All of theheat exchangers of vehicle 101 may be of this type. The heat exchanger107 is characterized by having a flow stabilizing area 171 near theinput air 176. The airflow stabilizes to more laminar flow within thestabilizing area before it leads into the heat exchange area 171. Theoutlet of the heat exchange area tapers to the downstream squirrel cageblower 173 that is driven by an electric motor 174. The blower 173 orfan portion in this case acts to pull the air inwards. The stabilizedflow allows for tighter tolerances in the blower 173 that in turn allowsa smaller electric fan motor 174 to be used.

The location of the transmission heat exchanger 106 and/or the HVAC heatexchanger 108 rearward of the cab 103 allows the efficiency of theseheat exchangers to take advantage of the negative pressure formed behindthe cab 103 during forward movement.

The energy management system may involve a main vehicle enginecrankshaft mounted generator 105. This simple generator 105 creates highvoltage direct current (DC) electricity. In one embodiment, thisgenerator 105 is mounted directly to the forward portion of thecrankshaft 105 of the engine 104 and also provides the crankshaft 119dampening function to the engine 104. A separate vibration mount usuallyprovides this dampening function in the prior art.

The high voltage DC generated by the crankshaft-mounted generator 105may be converted to household level AC (115VAC) for the operation ofcustomer application equipment. In one embodiment, the converter 123 isa closed loop switch mode converter 123 that makes the conversion of DCto AC alternatively turning ON and OFF at a varying frequency in orderto produce a time averaged AC output. FIG. 6 pictorially shows the inputand output of the switch mode converter 123 and how it approximates atime averaged AC output. The input is a high voltage DC signal. Theswitch mode converter 123 turns alternatively ON and OFF very quickly,actually much more frequent then shown in the drawing. The rate ofturning ON and OFF is varied to provide a SIN wave output as shown. Theperiods of the lower rate of turning ON and OFF results in the valley inthe AC SIN wave output, whereas the periods of higher rate of turning ONand OFF results in the peak in the AC SIN wave output.

The crankshaft-mounted generator 105 is electrically connected to theswitch mode converter through cabling 131. The household or customerlevel AC output from the switch mode converter 123 is directed to thecustomer electrical bus 132 that is provided at the OEM level. Customerapplication equipment 191 is powered using this household AC. A portionof the household or customer level AC from the customer electrical bus132 is converted to lower voltage DC through transformers or rectifiers124. This low level DC output from the transformers or rectifiers 124 isused to power cab instruments and controls 142 through low power bus 133and a higher level output from the transformers or rectifiers 124through engine control power bus 134 may be used for next generationengine controls 141.

The energy management system's use of the ON-OFF closed loop, orotherwise known as a switch mode converter, 123 in a vehicle 101 isunique. Similarly, the energy management system's use of a larger numberof smaller single function heat exchangers and associated electric fansprovides unique advantages such as flexibility about the location of theheat exchangers in areas other than the front of the vehicle andenhanced efficiency due to tolerance reduction with the common mountingareas for fans and heat exchangers.

A second embodiment of an energy management system made in accordancewith this invention is shown in FIG. 5. There is a vehicle 201 comprisedof a chassis with frame rails 202 a and 202 b which support a passengerand vehicle cab 203 and an engine 204. The engine 204 is coupled to atransmission 206 a to drive the vehicle 201. There may be a direct drivegenerator 205 directly engaged to the engine 204.

The transmission 206 a may be cooled by a transmission heat exchanger206 mounted to the rear of the cab 203. The rearward mounting of thetransmission heat exchanger 206 results in more room in the area forwardof the cab near the engine but it also results in a significantreduction in direct ram input air to the heat exchanger 206. Oneinnovation to the transmission heat exchanger 206 or any rear-mountedheat exchanger may be the addition of an air deflector 236 at the outletof the heat exchanger. This air deflector 236 causes a disruption orrerouting of the slipstream airflow E around the vehicle 201. The resultis that a low-pressure zone B is formed at the heat exchanger outletthereby facilitating the inlet air flow D entry into the inlet of theheat exchanger 206.

A heating ventilation and air conditioning (HVAC) heat exchanger 208 mayalso be located to the rear of the cab 203. This HVAC heat exchanger 208is engaged to the HVAC compressor 218. The HVAC heat exchanger 208 mayalso have an air deflector 238 at the outlet of the heat exchanger 208.This air deflector 238 also causes a disruption or rerouting of theslipstream airflow E around the vehicle 201. The result is that alow-pressure zone A is formed at the heat exchanger 208 outlet therebyfacilitating the inlet air flow C entry into the inlet of the heatexchanger 208.

An engine turbo-charger heat exchanger 210 with a separate electric fanmay provide cooling to an engine turbocharger 220 of the engine 204.

One aspect of this invention may include the balancing of heat loads ofindividual heat exchangers so as to maintain the fan motor sizeassociated with the respective heat exchanger at power level so as notto overtax the electrical system during fan start cycles. Fan startingcurrent peaks initially. The heat load balancing is demonstrated in FIG.5 in the engine coolant or water heat exchanger 207 and the engine oilheat exchanger 209. The engine coolant heat exchanger 207 providescooling to the engine 204 through the water pump 217. The engine coolantsystem operates under a defined capacity or volume of fluid that may beconsidered an engine coolant sump 227. The water pump 217 may beelectrically driven in one embodiment in order to allow energy savingson pump run time. The engine oil heat exchanger 209 provides cooling tothe engine 204 through the engine oil pump 219. The engine oil pump mayalso be electrically driven in one embodiment. The engine oil systemoperates under a defined capacity or volume of fluid that includes andengine oil sump 229. The load of the heat exchangers 207 and 209 may bemade close to each other by increasing the fluid capacity of one sump.The more capacity a sump has the less that heat exchanger has to cool asthe sump itself acts to provide heat exchanging effect. The systemdesigners adjust the sump capacity of the oil and coolant systems suchthat the load on the engine oil heat exchanger 209 approximates the loadon the engine coolant heat exchanger 207. This balancing allows forsmaller electric motors and hence causes less of a drain on the overallelectrical system.

An electric air compressor 251 may be used on the vehicle 201 for airneeds in lieu of an engine direct driven air compressor that runsconstantly. The electric air compressor 251 would only operate when airpressure was low hence saving on engine energy use.

The energy management system may be controlled by an electronic controlmodule 197 to ensure that the generator and engine combination is neveroverloaded. This control scheme involves the cycling of the electricfans and motors such that this equipment only operates when needed andall the equipment does not operate simultaneously. For instance in onescheme of operation, on initial startup the systems might be in thefollowing operational modes: Equipment Status Engine Oil HX Fan OFFEngine Coolant HX Fan OFF HVAC HX Fan OFF Turbo HX Fan ON TransmissionHX Fan ON or OFF (load dependent) Air Compressor ON Coolant Pump OFF OilPump ON

As the engine and vehicle warm up and the vehicle is operated, heatloads increase and the electronics on the vehicle will sequence on theabove equipment such as to never overload the generator and engine.During this warm up period, the generator and engine are available toprovide energy to equipment that might not be needed later. Forinstance, the electric air compressor might be used to charge the airpressure for vehicle brake operation. Once charged, the air compressormay be de-energized until air used for brake operation. As the vehiclecontinues to move, the engine, transmission, and turbo charger will heatup, and the vehicle electronics may sequence on electric poweredequipment to the following configuration: Equipment Status Engine Oil HXFan ON Engine Coolant HX Fan ON HVAC HX Fan OFF Turbo HX Fan ONTransmission HX Fan ON Air Compressor OFF Coolant Pump OFF Oil Pump ON

As the vehicle picks up speed, ram air due to vehicle motion andaerodynamic formation of low pressure zones on heat exchanger outletswill reduce the need for fan operation due to the vehicle motion inducedcooling air flow. As a result the vehicle electronics may cycle electricequipment as follows: Equipment Status Engine Oil HX Fan OFF EngineCoolant HX Fan OFF HVAC HX Fan OFF Turbo HX Fan ON Transmission HX FanON Air Compressor ON or OFF (depending on brake usage) Coolant Pump ONOil Pump ON

The above sequencing may be designed to prevent generator and engineoverloading.

Another embodiment of the energy balancing of this invention isdemonstrated in FIG. 7. In this case the focus is on improvingefficiency of emission control equipment for vehicles. The USEnvironmental Protection Agency has stepped up its enforcement of dieselengine emissions. The most recent regulations entitled 2004 rules wereactually initiated in Fall 2002. The next set of even more stringentregulations is anticipated for implementation in 2006 and 2007. It isanticipated that all diesel powered vehicle exhaust systems will havesome form of engine emission control exhaust after treatment system 192in order to comply with these regulations. These systems may be aparticulate trap, a NOX absorber, a NOX adsorber, or other catalyticconverter. Many of these emissions control systems 192 use rare orprecious metals or other catalytic substrates, such as platinum toassist in the catalytic reaction. These rare or precious metals haveoptimum operating temperatures that upon being heated to highertemperatures than the exhaust temperature will perform much moreefficiently in emissions control than when not heated. The issue withdiesel engines is that upon initial startup, especially in cold weather,the engine exhaust gases 198 are cold hence inhibiting the catalyticeffect of the catalytic substrates. If these catalytic substrates withinthe emission control systems 192 may be heated, for example to severalhundred degrees for platinum, then the emissions control systems willoperate much more efficiently to provide cleaner after-treatment gases199. The embodiment of FIG. 7 takes into account that with the shift toelectric motor for the fans for the engine oil, and engine coolant heatexchangers and electric motor for the water pump, the initial electricusage on the vehicle will be less. This will provide the opportunity toapply “raw” unregulated DC output from the generator 105, which isdirectly driven by the engine 104 to relatively high capacity electricheaters 193 for heating the catalytic substrates within the emissionscontrol systems 192. The advantage of an unregulated source will be thatthere will be no reduction of the power due to resistive losses througha regulator. The engine exhaust gases 198 will be sufficiently heated toself-warm the catalytic substrate by the time the need starts to arisefor electric fans for the engine oil and engine coolant heat exchangerelectric fans as well as the electric water pump to energize, henceproviding an energy balance within the vehicle. The added advantage isthat the use of electric heaters within the emissions control systemswill allow for use of less of the precious or rare metals or exoticcatalytic substrates. This will improve on overall costs to manufacturethe control systems 192 as the cost of the precious or rare metals orexotic catalytic substrates is a significant contributor. Additionally,the reduction in the amount of precious or rare metals or exoticcatalytic substrates should allow for smaller size emission controlsystems 192, allowing for improved flexibility.

Today diesel engine original equipment manufacturers (OEM) anticipatethat in order for vehicles to comply with the 2007 EPA regulations,after treatment systems will include Diesel Particulate Filters (DPF) orNOX adsorbers or both. It is also anticipated that these type emissioncontrol systems 192 may require short-term heat recycling periods orlong term recycling periods or both for their respective catalysts.These recycling or regeneration periods may involve heating of thecatalysts to either displace or burn sulfur or transform NOX, nitrousoxide to non-harmful compounds. The periodicity on the short-term andlong-term recycling periods will be variable based upon a number offactors including miles traveled, and fuel consumption. A vehicle orengine electronic control module (ECM) 197 may monitor both of thesefactors as well as others through the vehicle multiplexing communicationsystem. In one embodiment, the ECM 197 can provide the control toenergize or de-energize the heaters 193 upon cold startup conditions orupon the ECM's sensed need of either a short-term or long term recycleperiod. In the alternative, the ECM 197 may be used to provide thedriver notification of the need for a recycle period in the cab 103, atwhich time the driver could manually initiate a recycle operation of theheaters 193. For normal or cold startup of the engine, the ECM 197 mayalso monitor either catalyst or exhaust temperatures to determine theneed for energizing the heaters 193 and either automatically energizingor providing the driver indication of the need to manually energize theheaters 193.

As described above, the vehicle energy management system of thisinvention and a vehicle with this system installed provides a number ofadvantages, some of which have been described above and others of whichare inherent in the invention. Also modifications may be proposed to thevehicle energy management system of this invention and a vehicle withthis system installed without departing from the teachings herein.

1-19. (canceled)
 20. An energy management system in combination with amobile vehicle, comprising: a chassis and a cab engaged to said chassis;an engine engaged to said chassis and said engine engaged to atransmission for providing motive force on said vehicle; an exhaustsystem engaged to the exhaust output of said engine; a generator engagedto said engine for providing electricity to an electric system of saidvehicle; and said generator having an unregulated DC electricity outputand said generator electrically engaged to energize heaters of acatalyst within an engine emission control exhaust after treatmentsystem with said unregulated DC output.
 21. The vehicle and energymanagement system combination of claim 20, wherein: vehicle controlsenergize said catalyst heaters upon vehicle startup and de-energize saidcatalyst heaters upon catalyst warming.
 22. The vehicle and energymanagement system combination of claim 20, comprising: vehicle controlsenergize said catalyst heaters when said catalyst is cold andde-energize said catalyst heaters upon catalyst warming.
 23. The vehicleand energy management system combination of claim 20, comprising: anelectronic control module in communication with said vehicle electricsystem monitors vehicle parameters to determine a need for a periodicrecycle heating of said catalyst; and said electronic control moduleprogrammed to automatically initiate periodic catalyst recycle heatingupon sensing pre-determined parameters indicating a need for recycleheating.
 24. The vehicle and energy management system combination ofclaim 23, wherein: said parameters for determining a need for periodicrecycle heating includes fuel consumption.
 25. The vehicle and energymanagement system combination of claim 23, wherein: said parameters fordetermining a need for periodic recycle heating includes vehiclemileage.
 26. The vehicle and energy management system combination ofclaim 20, comprising: an electronic control module in communication withsaid vehicle electric system monitors vehicle parameters to determine aneed for a periodic recycle heating of said catalyst; and saidelectronic control module programmed to provide a visual indication insaid cab of said vehicle indicating a need for a manually initiatedrecycle heating of said catalyst.
 27. The vehicle and energy managementsystem combination of claim 26, wherein: said parameters for determininga need for periodic recycle heating includes fuel consumption.
 28. Thevehicle and energy management system combination of claim 26, wherein:said parameters for determining a need for periodic recycle heatingincludes vehicle mileage.
 29. An energy management system in combinationwith a mobile vehicle, comprising: a chassis and a cab engaged to saidchassis; an engine engaged to said chassis and said engine engaged to atransmission for providing motive force on said vehicle; a generatorengaged to said engine for providing electricity to an electric systemof said vehicle; an engine oil heat exchanger engaged to said chassisfor providing cooling to oil circulated to said engine within an engineoil system; said engine oil heat exchanger having an electric fanpowered from said electric system of said vehicle; a separate enginecoolant system heat exchanger engaged to said chassis for providingcooling to liquid coolant circulated to said engine within an enginecoolant system; said engine coolant system heat exchanger having anelectric fan powered from said electric system of said vehicle; an HVACsystem for providing comfort to said cab; a separate HVAC heat exchangerwithin said HVAC system to cool air for circulation to said cab; saidHVAC heat exchanger having an electric fan powered from said electricsystem of said vehicle; a turbocharger engaged to said engine; aseparate turbocharger heat exchanger engaged to said chassis to coolsaid turbocharger; said turbocharger heat exchanger having an electricfan powered from said electric system of said vehicle; and said fans oneach of said heat exchanger controlled to energize only when heat loadrises to predetermined levels and said fans controlled to sequentiallyenergize to avoid overloading of said generator.
 30. An energymanagement system in combination with a mobile vehicle, comprising: achassis and a cab engaged to said chassis; an engine engaged to saidchassis and said engine engaged to a transmission for providing motiveforce on said vehicle; a generator engaged to said engine for providingelectricity to an electric system of said vehicle; separate heatexchangers with separate electric fans powered from said electricsystem; and said fans on each of said heat exchanger controlled tosequentially energize to avoid overloading of said generator.